Thread take-up device



Dec. 11, 1945. c. R. BACKLIN THREAD TAKE-UP DEVICES Filed Nov. 5, 1941 s sheets-sheet 1 Hmmm h -ULIUUUUUUU INVENToR Clarence R. aw/(ZL BY ov? )704k V noRNEYs Dec. 1l, 1945. c. R. BACKLIN THREADTAKE-UP DEvIcEs Filed Nov. 5, 1941 5 Sheets-Sheet 2 BY y l ZATI'ORNEYS i Patented Dec. 1l,

Clarence Robert Backlln, Floral Park North, N. Y., assignor to Willcox & Gibbs Sewing Machine Company, New York, N. Y., ya corporation of New York application November s, 1941, serial No. 417,895

` s claims. (ci. ual-248)" -up element 'but also being so designed and so associated with the movable take-up element that it functions in maintaining thread to be coni of Fig. 4.

Fig. 6 is an exploded view of the unitary portion of the thread control means shown in Fig. e.

Fig. 'l is a `view similar to Fig. 2, 'but showing a modified form of the invention.

trolled in proper association with the latter ele- A menti Another feature of the invention resides Ain the provision in the thread control means of a movable take-up element and take-up guard combination of the immediately foregoing character in which the guard is providedwith means enabling' ready access to the thread in association l with the take-up element, for example, in the event the thread should` become broken or adversely wrapped about the take-up element.

Another feature of the invention resides in the provision of a take-up guard and movable takeup combination-in which the movable take-up includes a movable take-up element having al free end, and in which the guard forms one wall of a thread compartment, is resiliently distortable to permit thread being introduced in the compartment and into association with'the takeup element and is provided with means for maintaining the thread against slipping of! the free end of the take-up element.

Other features of the invention reside 'in the provision in the .take-up means of an adiustably mounted movable take-up element including a main .thread-engaging Section which is eccentric relative to the mounting section thereof, and in the provision of a guard plate for the movable take-up element, mounted for pivotal movement from an operative thread-confining and take-up shielding position to an open pomtion remote from the take-up element.

Other objects, features and advantages will hereinafter appear.

In the drawings:

Figure 1 is arear side .view of the head portion of a sewing machine embodying the present invention, certain conventional parts being omitted for clarity of illustration. Y

Fig. 8 is a view similar to Fig. 3, but showing the modied form of Fig. 7.

Fig. 9. is a fragmentary view of the hinge con nection embodied in the form shown in Figs. l and 8.

Fig. 10 is a side view of the take-up plate and take-up element as embodied in Figs. 'I and 8.

Fig. 11 is an enlarged fragmentary.. viewlooking toward the face of the take-up plate and take-up element of Fig. 10.

Before describing the present improvements and mode of operation thereof in detail it should be understood that the invention is not limited to the details of construction and arrangement of parts shown in the accompanying drawings. which are merely illustrative of the present preferred embodimentsl since the invention is capable of other embodiments, and the phraseology employed is for the purpose of description and not of limitation.

Referring more particularly lto the drawings construction thereof may be of any suitable formA and, perse, forms no part of thev present invention. c

As is usual, the presser foot bar il may be mounted for longitudinal movement from a low.- ered operative position to a raised inoperative position and normally maintained in a lowered operative position by means of any suitable spring, not shown. A hand lever II having a cam surface I6 operable onalaterally extending lifting arm I'I on the presser foot bar may be. pro- Avided for raising the latter element against the action of itsfpressure spring.` w f A y v In addition, av second lever Il suitably mounted for pivotal movement on the sewing machine frame and provided with an arm I9 having a linger thereon overlying the lifting arm I1 and underlying an upwardly oset portion 2I on the same arm I1 may be and, as shown, is provided for raising the presser foot bar. Any suitable connection, as through a link 22, may be lprovided for connecting the lever I8 to an operating means such, for example, as a conventional foot treadle, not shown.

For taking up and controlling a needel thread 23 during the stitching operations, there is provided a main take-up mechanism 24`of the present invention. The machine also has a cooperable secondary take-up mechanism 25 and tension device which are not specifically claimed herein. As is conventional the main take-up mechanism may include a main movable thread-engaging take-up element 23 positively operated through a cycle of movement, while the secondary take-up mechanism may include a resilient take-up element 21 located intermediate a.- thread tension means 28 and the main take-up element. The function of these elements in controlling the needel thread is well understood in the sewing machine art, particularly as applied to sewing machines of the lock stitch type.

4As shown, the main take-up mechanism 24 is of the class known in the art as a rotary take up and includes, in addition to the thread-engaging element 26, a take-up plate-23 secured, as by a screw 30, to the end of a usual rotating top shaft 3| mounted in the sewing machine frame and rotatable therewith. The take-up element 23, which is connected to the take-up plate at a point offset radially from the rotative center thereof, thus is movable in a rotary path with the shaft 3I as a center.

According to the present invention the take-up element 26, which may be in the form of a pin, projects outwardly from the outer face of the take-up plate and terminates in an enlarged free end 32. As shown,.the inner end 33 of the pin may be of reduced size, extending through a hole lin the take-up plate and iixed to the latter by a shoulder portion 34 and a pressed over or riveted portion 35. Y

Also, asshown, the end wall 36 of the sewing Serving as aguard-plate-steadying meansand as a thread-confining means adjacent the upper portion of the guard plate, is a linger 43 of substantially hook shape which extends outwardly from and, as shown, may be integral with the sewing machine frame. The free end 44 of the linger preferably is rounded and ilts in a complementary dimple 45 in the guard plate. With this construction the guard plate, which advantageously is of resiliently bendable material, maybe deected inwardly at the upper free end portion plastic material, preferably transparent to permit visual inspection of the thread compartment, may

machine frame may be recessed at 31 to receive tially flush with each other.

Of particular importance there'is associated with the take-up plate 23 and take-up element 2l, a guard plate 3l which not only serves to shield the moving parts o! the main take-up mechanism but also serves together withthe end wall 38 and the take-up plate 23 to provide a-thread compartment 30, and is formed with a groove-in the inner twen the end wail and the lower portion` of the guard plate to space the later outwardly relative to the take-up plate and thus provide the thread compartment 33. Also, and as shown. a llpllke ex'tensionisformedonthesewingmachinetrame.

at one side ot the guard plate to provide a guard 01 to-prevent slack thread from adversely being thrown out of the thread compartment and away xromithe take-upmechanism.

advantageously be utilized in the construction of the guard plate.

Preferably, and in order that'a most eiective action of the main take-up mechanism 24 may be achieved, a suitable thread guide 46 is interposed between the resilient take-up element 21 and the main movable take-up element 26 and so positioned relative to the path of the latter and to another suitable and usual guide I3a provided on the needle bar I3 that the thread 23 when passed over the main movable take-up element, as shown, forms a close inverted V-shape. Y 0f importance, to enable ready access to the thread in the compartment 39 should it become broken or adversely wrapped around the take-up element 26 apertures 41 and 48 are advantageously provided in the guard plate. As shown, one of these apertures 48 is located centrally of the circular raceway and opposite the rotative center of the take-up plate 29, and the other aperture 41 is located above the mst-described aperture to intersect the-raceway 40 and make possible direct access to the take-up element 26 when the latter is in the position shown in Figs. 2 and 3. l

To balance the take-up plate 23,holes 43 and 50 may be formed therein as shown, the size being determined after assembly with the take- -up element 26.

'I'he resilient take-up element 21 of the secondary take-up mechanism 2,5, see particularh in Figs. 4, 5 and 6, is in the form of a helically coiled spring having a connecting end portion 5I disposed to extend in a direction longitudinally of the coil and another end portion 52 extending laterally from the coil and terminating in a thread-engaging-hooklike section 53.

' 0f importance the secondary. take-up meclia- .nism 25 is so constructed that a single adjusting member 54 is adapted to control notronly theA amount of take up eiected by the resilient element 21 but also the spring loadingof this element. Y

Also, of importance this secondary take-up mechanism 25 and the thread-tension means v2l are associated in an especially compact and easilyA adjustable thread-control unit B5. l A 'lhis controlunit 55 advantageously is, mounted on the sewing machine frame by a 'stud It passing through matching bores in spaced webs 51 and 58 which may be formed integral -with the frame. Also, and as shown, this same stud 5l may serve as the pivot i'o'the presser bar.`

lifting hand lever .Il which isv mounted for arcuate movement thereon intermediate the spaced webs 51 and Il.

Mounted on the stud and iltting partially in a recess 53 in the outer face of the web Il is one tension plate 80 of the thread-tension means 28. Opposed to the tension plate 88 and also mounted on the stud is a second-tension plate I which, through an intermediate-tension wheel 62 and compressible washers 53 and 54, cooperates with the nrst tension plate in controlling the tension on the thread. Rotation of the second-tension plate 5I on the stud is prevented by a locking pin 55 which passes through a transversely extending hole 56 in a hublike extension 51 of the second plate and through a slot 58 extending longitudinally of the stud. It will be readily appreciated that if the second plate 5I is lightly pressed towards the first plate, the washers 53 and 64, which preferably are of felt or the like, will exert a relatively light gripping action retarding the rotation of the tension wheel on the stud, while if the second plate is urged toward the first plate with greater pressure the washers will exert a greater retarding action on the tension wheel. Supplemental to or I.alternative to the retarding action -of the washers in frictionally gripping the tension wheel, tension .may be applied to the thread by friction exerted directly on the thread by the opposed marginal portions 59 and 15 of the tension plates as the thread passes therebetween to and -from the wheel 82.

Of particular importance, in associating the secondary take-up mechanism 25 with the stud, the coiled spring constituting the resilient'takeup element is located on the hublike extension with the vconnecting end portion 5| secured in a ously, and as shown, a turning head 88 located outside of the annular chamber 80, is provided on the controlling member.

Completing the association of the control ,unit 55 with the sewing machine frame is a holding nut 81 screwed on a threaded portion 88 on the inner end of the stud and up against the web 51.

For enabling an automatic release of the threadtension means 28 upon a raising of the presserA foot bar I4 there is a tension release pin 88 located in a bore 98 extending longitudinally of the stud from its inner end to communicate with the slot 58 which is aligned therewith. One end of the release pin 89 abutsthe locking pin 55 in the slot 58 and the other end projects beyond the in-v ner end of the stud.- It will be readily understood that longitudinal movement of the release pin in a direction towards the spring ..8I will retract the tension plate 5I relative to the tension plate 58 thus releasing the tension'on the thread.

An advantageous means for eiecting this releasing movement oi the pin 89 is provided by a tension-releasing finger 8l on the presser foot lifting lever I8 and so disposed relative to the projecting end of the release pin 88 tha-t, while it is normally spaced from the latter, Amovement of the lever I8 to lift the presser foot bar will concurrently move the finger to engage the release pin selected one of a plurality of varcuately disposed holes 1I in the hub portion 12 of the adjusting member, and with the other end portion 52 extending outwardly through an arcuately extending slot 13 in an outer angelike portion 14 of the adjusting member. "The resilient take-up element 21 is so adjusted and associated with the adjusting member 54 that the laterally extending portion 52 thereof is yieldingly urged in such a way as to normally abut against the end wall 15 of the slot. This end wall 15, therefore, serves as a stop to limit the retracting or take-up motion of the thread-engaging section 53.

It is to be noted that the'angelike portion 14, the hublike extension 51, and theouter marginal face of the tension plate, together define a substantially closed annular chamber 15 in which the main body of the take-up spring 21 is conned and-shielded, and that the hub portion 12 is mounted for rotative adjustment on the extension. A set screw 11 in the hub portion and engageable with the extension 51 serves to lock the adjusting member relative to the latter.

Also of importance, the hublike extension 51 is provided with an enlarged bore 18 open at its outer end and terminating at its other end in an and urge it in a tension-releasing direction. Also, because of the relation of the cam surface I5 on the hand lever I5 with the lifting arm I1, it will be readily yappreciated that a presser foot bar lifting motion of the hand lever I5 likewise will cause the tension-releasing nger 48l to move the pin 89 in a tension-releasing direction against the pressure of the tension spring 8 i Of importance, when it is desired to alter `the I. amount of take-up eiected by the resilient take' up element 21 itis merely necessary to back on the set screw 11 on the adjusting member 54 and turn the latter arcuately on the hublike extension 51 of the nonrotating tension plate 6I to adjust the position ofthe take-up limiting wall 15 of the slot.

Also, and of particular importance, when it is desired to alter the spring loading of the resilient take-up element, it is merely necessary to insert .the connecting end portion 5I .thereof in a differ-- ent one of the arcuately disposed holes 1I in the same adjusting member 54. In this manner the spring force normally maintaining 'the laterally extending portion 52 against the take-up limiting end wall may be increased or decreased depending on whether the connecting portion is moved clockwise or counterclockwise of the adjusting member as viewed in Fig. 5.

Such adjustments of the resilient take-up element 21 .to cause the same to take up or control a greater or a lesser extent of slack thread and to annular shoulder 19 to provide in effect a sleeve-'1" like projection on the second-tension plate 5I. Located inan annular chamber 88 dened by the sleevelike projection and the stud, and abutting the annular shoulder 19, is a resilient element, as

shown in the form of a coiled spring 8|, for yieldingly urging the second-tension plate 5| toward the first-tension plate 58. A manually ,operable spring controlling member 82 having internal threads 83 cooperable with threads 84 on"tl ie outer end of the stud and formed with a portion 85 adaptel to ilt into the annular chamber 88 is provided for adjustably controlling .the loading of the spring 8l and thus adjustably controlling the tension of the thread tension means. Advantageeiect a stronger and quicker or a weaker and slower spring action, depending uPOn the character of the work, the strain desired on the thread and the speed of the sewing machine, as will be well understood in the art, are highly important and desirable. With the present invention the particularly advantageous and compact control unit 55 is provided which not only embodies a thread-tension means and a resilient take-up lmeans but also includes mechanism by which these means may be easily and readily adjusted.

In associating the needle thread 23 with the several cooperating thread control means hereinabove described, it may be drawn fromany suitable supply, not shown, and passed through a conventional thread guide 82 to a conventional tension cup and guide ss anu u the control una 55. There it is passed around the tension wheel 62 in the usual-manner, and then over the aligned hooklike thread-engaging section 53 of the sec-v ondary take-up mechanism 25. From :the secondary take-up mechanism the thread passes through the guide 46 and thence up through the thread compartment over the main movable takeup element 26 and down to the needle.

It is to be particularhr noted that the thread Y may be most easily associated with the main take-up element in the thread compartment by merely holding the same in a simple loopAand sliding it under the rounded end f the confining finger 43 and over the upper edge of the guard plate into the thread compartment where it loops automatically over the main take-up element in a groove 94 dei-ined 'between the enlarged end 32 and the take-up plate 29. Because of ment over the upper-end of the4 guard by the conning finger 43, against movement over the lower end of the guard Iby the spacer element 42, and against adverse movement off the enlarged confined against movement-out of the cmpartfree'end 32 o f the take-up element through the l employment of the free end receiving raceway in the guard which thus locates the free end outside ofthe compartment 39 in which the thread moves.

If desired and as embodied in the vmodified form shown in Figs. 7, 8, 9, 10 and l1, a guard Plate 98a may be associated with the main takeup mechanism, which, unlike the guard plate-38 shown in Figs. 1-3 is not secured directly to the sewing machine frame as by the screws 4|, `but is hingedly secured to the sewing machine frame so that it may be bodily swung outwardly away from lthe end wall 36 thereof and the take-up plate 29. Such an arrangement is advantageous in that it facilitates access to the take-up mechanism especially for purposes of cleaning, repair and getting at thread that may become adverseLv woimd up thereon. and also for the purpose of In this construction lthe hingediiconnection, as shown in Figs. 7, 8 and 9, is provided by a pivot stud 90 passing through spaced de' pending ears 90 and |00 on the sewing machine frame' and an upwardly extending ear I0|` on a swing bracket |02 to which the guard plate 38a For securing the guard plate 38a to the swing bracket arm |04 a plurality of screws |05 may be used, which same screws advantageously also serve to secure a spacer element 42a to the inner side of the guard plate to thus space the latter outwardly from the end wall 36 and, as in the case'of the construction shown in Figs. 1-3, provide the thread compartment 39. As shown, the spacer element 42a and swing bracket |02 may be of metal. Also, and as shown, the outer face o f the guard plate 38a may be formed with a recess |09 for receiving the arm |04 of the swing bracket.

Serving to normally maintain the 'guard plate 38a in its operative position there is provided in a confining extension 43a on the sewing machine frame, a round ended shouldered pin |01 backed.

by a spring |08 and adapted 'to 4engage in a dimple |09 formed in a projection I0 adjacent the upper end of the guard plate. nection thus provided, it will be appreciated, simple, effective and automatic.

In order that the thread guide-46, which is similar to the corresponding guide in the form shown in Figs. 1 6, mayv not interfere with the swinging of theguard .plate between an upper operative to an outer and lowered position, aligned slots are formed in 4the arm |04 of the swing bracket, in the guardplate and in the spacer element to provide a thread guide clearanceopeninglll. i i i While 'as shown, the swing bracket |02 and guard plate 38a may be formed as two separate lelements secured together, it will be appreciated that the guard plate and swing bracket may be made of a one-piece integral construction, as of metal.

Also, if desired and as embodied in the modified form shown in Figs. 7, 8, 9, 10 and 11, there may be 'provided a modied main take-up element 26a which is mounted in a way enabling ready adjustment thereof relative to the take-up plate 29 on which it is mounted to thus vary the extent of take-up on the thread.

Advantageously, and as shownbest in Figs. l0

and 11, this adjustable mounting is eiected by forming the take-up element with a main threadengaging head 32a which is eccentric relative to i the reduced mounting shank 33a thereof which extends through a matching hole in the take-up plate. Hence, when the take-up element is adjusted rotatably, the position of the thread-engaging head thereof will be varied with respect to the rotative center of the take-up plate 29 which is the sameconstruction andis associated with the shaft 3| in the same manner as the take-up plate first In'fFig. 1l several positions l of adjustment are illustrated by dotted lines.

To facilitate this adjustment of the take-up element a slot ||2 adapted to receive a screw driver -or other suitable tool, preferably is provided in the head 32a. and-a spring washer lll is is secured. Advantageously this swing bracket is substantially L -shaped with an arm |03 adapted to extend outwardly beneath the sewing machine frame and an'arm |04 adapted to extend upwardly. when the bracket is in its normal or operative position as shown in Figs. 7 and 8.

The guard plate 00a, apart from the manner of its association with the sewing machine frame isvessentially the same as the guard fplate 30. being preferably formed of a. suitable transparent and resiliently bendable plastic material and having a raceway 40 and apertures 41 and 40 provided therein.

inserted between ariveted over end 35a on the mounting shank and the take-up plate 20. Ad-

vantageously, and if desired, suitable markings may be provided on the take-up plate to indicate the adiustment'eifected.

In all other particulars the construction and operation of the modiiied form shown in Figs. '1, 8, 9, 10 -and 11,-is exactly the sameas inthe form shown in Figs. 1-6. it being understood that when the eccentrlcally adjustable take-up' clement is utilized, the raceway in the guard plate is made or sumcientwidth to permit adiustmen of the take-up element. l

The snap'conl end, carried by and projectingfrom said plate,l

for operating on thread from said guiding means; a normally stationary take-up guard carried by said frame, spaced from said plate to provide a .thread compartment, and having a raceway for receiving said free end; and means on said frame for confining said thread against movement out of said compartment over the edge of said guard, said conning means and said guard being normally maintained in yielding engagement.

2. In a sewing machine, the combination of thread-guiding means; a rotary take-up plate; a take-up element having .a free end, carried by and projecting from said plate, for operating on thread from said guiding means; a normally stationary take-up guard, spaced from said plate to providea thread compartment, and having a raceway for receiving said free end; and means for confining said thread against movement out of raceway formed therein for receiving said free end; means opposed to and spaced from said guard plate to denne with the latter a thread compartment with the take-up element located said compartment over an edge of said guard, said coniining means and said guard being mainlocating said thread relative to said take-up element; and confining means on said frame andl ingly movable relative to said confining means to permit said thread from said guide means to be loopedI over an edge of said guard plate into said compartment and relative to said take-up element. I

4. In a sewing machine, the combination of a frame; a rotary take-up plate; a take-up element having a free end, carried by and projecting from said plate, for operating on a thread; a guard plate opposed to said take-up element and takeup plate and spaced outwardly from" the latter to provide a thread compartment, said guard plate having a raceway for receiving said free end; and a liplike extension formed on said frame and extending out from the latter at one side o! said thread compartment and said guard plate for maintaining said thread against being thrown out of said compartment and away from operative association with said take-up element.

5. In a sewing machine, the combination of a rotatable take-up plate having a, center of rota# tion; a take-up element having a main threadengaging section with a free end and having a mounting section, said mounting section being mounted for rotative adjustment on said takeup plate at a point eccentric relative to the'center of rotation and being eccentric relative tosaid thread-engaging section; and a normally stationary guard plate having a raceway opposed to said free end for receiving the'same, adapted to maintain a thread relative to said main thread-- engaging section, said raceway being of suilicient width to permit said adjustment of said take-up element.v

CLARENCE ROBERT BACKLIN.

and movable therein; threadl guide means i'or 

